Microsatellite markers reveal high allelic variation in natural populations of Cryptomeria japonica near refugial areas of the last glacial period
Microsatellite markers reveal high allelic variation in natural populations of Cryptomeria japonica near refugial areas of the last glacial period
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DOI：
10.1007/s10265-005-0198-2
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发表时间：
2005-03
影响因子：
2.8
通讯作者：
Tomokazu Takahashi;N. Tani;H. Taira;Y. Tsumura
中科院分区：
文献类型：
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作者：
Tomokazu Takahashi;N. Tani;H. Taira;Y. Tsumura
利用11个微卫星标记，研究了柳杉自然分布区的等位基因变异和遗传结构。这些标记显示出高水平的多态性（平均基因多样性=0.77，平均等位基因数=24.0），与以往研究中等位酶和切割扩增多态性序列标记中发现的较低水平的多态性形成鲜明对比。居群间遗传分化较小（FST= 0.028，P <0.001），这可能与该物种为风媒传粉且寿命长有关。用主坐标法和未加权对组法进行算术平均分析，未发现Nei遗传距离与居群地理位置之间存在明显的相关性。这种趋势的缺乏可能部分是由于突变模糊了系谱记录所产生的微卫星同源性。然而，有一个高等位基因多样性的趋势，在5个人口（芦高，芦，冲岛，Yakushima岛-1和-2），这是非常接近，或在末次冰期的避难所定义的Tsukada根据花粉分析数据和当前的气候区划。我们假设，这些避难所人口可能受到遗传漂变的影响比其他人口，由于其相对较大的规模。
Using 11 microsatellite markers, we investigated the allelic variation and genetic structure ofCryptomeria japonica, across most of its natural distribution. The markers displayed high levels of polymorphism (average gene diversity=0.77, average number of alleles=24.0), in sharp contrast to the lower levels of polymorphism found in allozyme and cleaved amplified polymorphic sequence markers in previous studies. Little genetic differentiation was found among populations (FST=0.028,P<0.001), probably because the species is wind-pollinated and long-lived. No clear relationship between Nei’s genetic distances and geographical locations of the populations were found using the principal coordinate and unweighted pair-group method with arithmetic averaging analyses. The lack of such trends might be due partly to microsatellite homoplasy arising from mutation blurring the genealogical record. However, there was a trend towards high allelic diversity in five populations (Ashitaka, Ashiu, Oki-Island, Yakushima-Island-1 and -2), which are very close to, or in, refugial areas of the last glacial period as defined by Tsukada based on pollen analysis data and current climatic divisions. We postulate that these refugial populations might have been less affected by genetic drift than the other populations due to their relatively large size.